Having some issues with subnet

tpolich · 2010-07-07 03:14:47

Ok so am setting up a network and I have been running into a few kinks recently. I am trying to learn all this before I move into my new college apartment where I will be setting up our network.

What I am trying to do is set up a subnet inside my network. I think this graphic gives a better explanation

                                                    [the internets]   76.16.87.*
                                                               |
                                                             [ cable modem]
                                                             |
                                                             |
                                                        [arch linux router box]  192.168.5.252 netmask 255.255.255.0,  runs dhcp/dns server, and masquerades all traffic going out of the wan port
                                                             |
                                                             | (into lan port, it's wan is empty and disabled)
                                                    [linksys wireless router]   192.168.5.1, is not running dhcp
                                                    |            |
                                                    |            | 
                                                    |   [print server, arch linux box]  192.168.5.159, runs a cups server and provides printing
                                                    |
                                                    | (into wan port, wan static ip 192.168.5.200 )
                                              [linksys wired router]  192.168.2.1 netmask 255.255.255.248, runs dhcp server
                                              |                 |
                                        [ps3, dhcp]   [my pc, dhcp]

.

First of all I know the two subnets isn't needed at all. That doesn't changed the fact that I want to do it.

I then set up a static route on the linksys wireless router to take all traffic going to 192.168.2.0 and send it to 192.168.5.200 (the wired router).

I managed to get this set up working when I turned nat on the linksys wired router. But doing that means I am nating traffic twice which from what I read your not suppose to do. Can someone please explain how I would make this setup work without nating twice?

Thank you very much,

Tim

logd · 2010-07-07 03:51:24

I believe you could just use the same subnet for everything. If your unwilling to do so, then you need to tell your last router (wired) the gateway address it should use, which would be the router above that. And do it again for the router above that. The gateway address of the linksys wired router, will be the address of the linksys wireless router. And it's gateway address it should look for should be the address of the arch linux router box. IMO, this is all nuts, id just throw a lot of that on a switch.

Last edited by logd (2010-07-07 03:53:42)

hunterthomson · 2010-07-07 04:46:44

Well there are a # of ways to do what you want to do but if you ask me I'd do "Router On A Stick" setup with VLANs.

But the point of VLAN is to limit broadcast domains. However, you don't want to do that. You want the other computers to be able to Print right? Well one use I could see would be to put the Wireless AP on a different VLAN form your servers.

Well anyway.... To do that...

- Then use the Arch box as the Firewall/Router. Use this to route traffic from one VLAN to the other.

- Install DD-WRT on the Linksys routers so you'll have VLAN support.

- Set up the Wired Linksys as a VLAN Switch. Connect the servers and Desktops to VLAN 1 with IP 192.168.5.0/24.

- Then connect the Wireless AP to one port on the VLAN Switch and have it on VLAN2 with IP 192.168.2.0/24

----------------

Or you could just have the Archbox be a Firewall and use the Linksys as a Layer 3switch....

As much as I like Archlinux.. I think you mite be better off using like Shorewall or Smothwall. They will make is all much simpler to do the things you want and to setup QOS.

Last edited by hunterthomson (2010-07-07 05:00:54)

tpolich · 2010-07-07 07:40:15

Thank you for the help I got it up and running now but I have run into a two issues. I can ping out of the subnet to the larger network but not the internet even though I can browse the web.... i got no idea how that works.

I can't ping into my subnet from computers outside of it. Not sure what to do / make of this.

hunterthomson · 2010-07-07 07:50:42

Well I know routing on Cisco better, so I may be wrong about the exact commands.

If you set it up the way you describe in your first post.... Both of your problems are caused by one problem.

You need to set the route .... Well I guess just put it on the Arch Box,... the Wired Linksys dose have a 192.168.5.0/24 address on the WAN port right.. ya it must... I'll pretend it is "192.168.5.11" Also you will want to set Static IP's on the Server and the Wired Linksys.

WAN port on Wired Linksys = 192.168.5.11
Interface on Arch box that is connected to the LAN = eth0

route add 192.168.2.0 192.168.5.11 netmask 255.255.255.0 eth0... nope that is wrong
try this...
route add -net 192.168.2.0 netmask 255.255.255.0 dev eth0... hum that doesn't seem to work ether...

Well you get the Idea you need to set the route to that network

It would be easier if it was setup like this....

Cable Modem
|
|
123.45.67.89
Arch Box Firewall
192.168.1.1
|
192.168.1.0/24
|
192.168.1.2
Linksys Layer 3 Switch------------------------------------|
| | |
VLAN-10 | |
192.168.2.0/24 | VLAN-30
| VLAN-20 192.168.4.0/24
| 192.168.3.0/24 |
192.168.2.1 | |
Wireless AP | Server-2
| | 192.168.4.1
| |
Laptop-1 |
192.168.2.100 |
|
|--------------------------------|---------------------------|
Server-1 PC-1 PC-2
192.168.3.102 192.168.3.103 192.168.3.104

########################
Better yet
########################
Or put more NIC's in the Arch Box Then.....

Cable Modem
|
|
eth0
123.45.67.89
Arch Box Firewall / Router
| |
eth1 eth2
192.168.1.1 192.168.2.1
DMZ |---------------------------------------------------|
| |
Server (NOTE: at this point Virtualize the Server on Arch) |
192.168.1.2 |
|
Linksys Wired - Switch
| |------------------|
| | |
| | |
Wireless AP PC-1 |
| 192.168.2.110 |
Laptop [On WiFi] |
192.168.2.100 PC-2
192.168.2.120

Last edited by hunterthomson (2010-07-07 10:53:41)

Arch Linux

#1 2010-07-07 03:14:47

Having some issues with subnet

#2 2010-07-07 03:51:24

Re: Having some issues with subnet

#3 2010-07-07 04:46:44

Re: Having some issues with subnet

#4 2010-07-07 07:40:15

Re: Having some issues with subnet

#5 2010-07-07 07:50:42

Re: Having some issues with subnet

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